The present invention is concerned with a process for the removal of non-specific turbidities in the carrying out of determinations according to the immunoassay principle.
The development of determinations according to the immuno-assay principle has led to a decisive improvement in the sensitivity and selectivity in the case of the determination of specifically bindable substances, such as proteins, haptens and antibodies, and has, therefore, achieved great importance in clinical chemical laboratories. The further development of these methods starting from the radio-immunoassay led not only to the broadening of the available labelling methods but also to the development of various analysis techniques. Immuno-assays which use enzymes and fluorescing compounds as labellings are today widely used. The determination of the labelling, and thus of the substance to be detected thereby, depends upon a change of absorption or emission of light to be measured photometrically. It is a basic requirement of these processes that they provide a measurement signal which is directly proportional to the amount of the substance to be determined but, at the same time, a disturbance by components which are present in the solution to be investigated, for example serum, must be avoided with certainty. In addition, they must display a very high sensitivity so that sufficiently precise results can be achieved even in the picomole range. By means of these new determination processes, it became possible to detect substances in serum, the detection of which was not possible at all with the previously known analytical processes.
In the case of the detection of these substances present in very small amounts, for example TSH or AFP, it is naturally especially important to exclude all disturbances which lead to a falsification of the result. In the case of the determination of clinical parameters in serum samples or in standards which are prepared on the basis of serum, disturbances frequently occur due to non-specific agglutination. This non-specific agglutination leads to more or less slight turbidities which disturb the photometric evaluation. Hitherto, these non-specific agglutinations could not be completely eliminated either by the addition of chaotropic reagents or by the addition of detergents.
Therefore, it is an object of the present invention to provide a process for suppressing or dissolving non-specific agglutinations in serum samples.